Pump



Nov. 12, 1946.

N. A. CHRISTENSEN PUMP Filed July 7, 1944 @sheets-sheet 1 lvraenn Nov.12,'1946. N. A. cHRlsTENsEN 2,410,308

PUMP

n Filed July 7, 1944 2 Sheets-Sheet 2 IN VEN TOR. MH: A. CMP/515mmEffenaar:

through such pump;

Patented Nov. l2,

UNITED STATES PATENT ,OF-FICE y 2,410,808 i Y v l PUMP Niels A.Christensen, South Euclid, Ohio Application July 7, 1944, .Serial No.l543,869

(Cl. 103-193)r 8 Claims.

This invention relates to a double-acting piston pump, the generalobject being to lprovide such pump in a very simple form, eillcient forpropelling a continuous streamvof fluid. Another object is to providesuch a pump in the form which may be very readily disassembled forcleaning and reassembled, and will maintain itself tight in alllocations where leakage might be liable to occur.

More particularly, my invention provides a cylinder with two removableheads and a piston in the cylinder carrying a feeding conduit profjecting through one of the heads, the piston being hollow and havingvalve controlled passages to feed liquid to either side of the pistonaccording to the direction of movement thereof, so that liquid may bereceived within the pistonV and forced iirst to one end of the cylinderand then the other, two ends being connected through two suitable checkvalves to a common discharge pipe. It is an object of the. invention toprovide such a pump with simple and at the same'time effective valvemeans within the piston controlling the intake thereto and the dischargefrom the piston alternately to opposite ends of the cylinder.

The provision of a simple frame construction, readily separable but firmwhen assembled, and a simple and eiiective manual means forreciprocating the piston are also objects of the invention.

My invention is illustrated in two preferred forms in the accompanyingdrawings and its features will be more apparent from the'followingdetailed description of those forms, it being understood that I do notlimit myself to either specific form illustrated further than theappended claims and the prior art require.

In the drawings, Fig. 1 is a plan of a preferred form of hand operatedpump embodying this invention; Fig. 2 is a vertical central section Fig.3 is a cross section in a vertical plane. as indicated by the line 3-3on Fig. 2 looking toward the left; Fig. 4 is a vertical section throughthe piston shown in Fig'. 2; Fig. 5 is a vertical longitudinal sectionof my pump having a different form of piston and valves; Figs. 6 and '7are vertical cross sections of the pump shown in Fig. 5, the planes ofthe sections being indicated by the correspondingly numbered lines onFig. 5.

The body of the pump,'shown in Figs. 1, 2 and 3, comprises: a cylinder Iwith discharge passageways controlled by check valves; a pair ofcylinder heads and 2| adapted to seat in the `lill occupying a scotch 2cylinder and overlap the ends thereof; a pair of frame members 30 and 3|abutting the two cylinder heads, and a seriesof through bolts 40extending alongside ofthe cylinder and passing through the frame membersand having heads 4| at one end and carrying nuts 42 at the'other end.The tightening of these nuts clamps the frame plates against lthecylinder heads and th.

yheads against the ends ofthe cylinder, to makl av simple stationaryconstruction. Below the cylinder, the two frame plates are anged intohorizontal members 32 and 33 providing a suitable base carrying the pumpwith braces 32' and 33.

' Within the cylinder is a reciprocating piston 5|]v having on one sidea solid rod 5 extending through the cylinder head 20 and on the otherside a tubular rod 52 extending through the cylinder head L2|.` 'I'hecylinder head 2| is provided with va tubular extension, 22 internallythreaded at its end to receive a suction pipe 25'. Such suction pipecommunicates,A through the hollow rod 52 with the interior of thepiston, thus supplying liquid to the pump, as hereinafter explained.

The rod 5| provides the means by which the piston is reciprocated. Ihave shown the pump `as a hand operated device and in this case Iprovide an oscillating arm pivoted tothe base plate 32 and carried in anupwardly extending operating handle bar 6|. The oscillating member 6|)carries a cross pin 63 on which is a roller yoke 55 on the piston rod5I. The yoke is shown as having av strap portion with vertical parallelopposed faces engaged opposite sides of the roller 54 and havinganiinternally threaded tubular extension 56 threaded onto an externallythreaded reduced portion 51 of the piston rod 5|. A nut 58 on thisthread clamps the yoke tightly to the rod. i

As shown in the drawings, the pivoting of the operating member isaccomplished by a pair of frame ears 35 turnedupwardly from the baseplate 32 and carrying a cross pin 3l which occupies a tubular membercarried between and secured to the lower ends of the bifurcated arm 60.The bolt 31 is shown as having a head 38 on oneend and a nut 39 on theother. Similarly the bolt 63.carrying the roller 64 has a head 66 on oneend and a nut 61 on the other. The

upper ends of the bifurcated operating member are curved inwardly and ina nearly semi-circular form, as indicated at 68 to rigidly embrace theoperating handle 8|. It will be seen that 3 the reciprocation of thishandle operates to reciprocate'the piston within the cylinder.

'I'he piston 50 has within-it the two diametrically opposedcylindrically-shaped chambers 1I! and 1I. The chamber 10 communicateswith the portion of the cylinder toward the left, Fig. 2 (thatv 'istoward the operating member) by a port 12, while the cylinder 1Icommunicates at the opposite end of the cylinder by a port 13. The twochambers are both. connected with the bore 53 of the tubular piston rod52 by ports 'I5 and 1B.

Each port 15 or 16 is normally closed by a ball valve BI or 82 pressedinwardly by a compression spring ,35, the inner end of which abuts thevalve ball and the outer end of which abuts a stop plate 85 mounted inan enlargement of the cavity or 1I of the piston. An abutment member 86is a dished plate pressed inwardly to its seat sothat its edge iirmlyengages the wall of the cavity it` occupies, the plate thus forming aneffective abutment for the spring without engaging theI cylinder wall.The operation of these valves willV be described later.

Rigidly formed on the exterior of the cylinder, either as a part thereofor permanently secured thereto, is a body II having a longitudinalpassageway I2 communicatingcentrally-with a hollow boss I3 into which isthreaded the discharge pipe 30. The passageway |21 communicates atopposite ends with cavities Il and I5 which communicate respectivelywith opposite end portions f of the cylinder'by ports I5 and I1. The twoports IG and I 1 are normally closed by ball valves 9| and 92 which areshown as seated by springs 93. Each spring bears at its inner endagainst the corresponding ball and at the outer end seats in a cavity ina screw plug which is threadingly mounted in an internally threadedupwardly extending wall about the corresponding cavity Il or I5. yForconvenience of formation, I extend the passageway I2 in the bodyV IIentirely to one end of such body and close it by a removable plug 95.

I provide suitable packings to maintaina fluidtight connection betweenthe cylinder heads and the cylinder wall, as shown at |00; also betweenthe cylinder heads and the: piston rods, as shown at IUI; and betweenthe piston and cylinderwall at |02.

As shown, each of the packings comprises an annular` ring of rubber-likematerial normallyy round in cross section but somewhat flattened inposition so as to partially occupy a groove in the member carrying it,of somewhat greater width than the ring. By this means the packingmember` is able to roll as it is moved along its contacting member, orsuch member moves along the ring. This rolling action kneadsrthematerial of the ring and maintains it in active condition over a longperiod of time. The rolling of the outer packing, in the cylinder headsoccurs whenever such heads are put into piace in the cylinder and isalso kneaded by pressure variation from the alternate pressure andintake strokes, and as to the other packings occurs with each stroke ofthe piston. v

In the operation of the pump, shown in Fig. 2, if the handle 6I is movedto the left, reduced pressure results in the chamber A at the right ofthe piston. This results in the valve 82 lifting, while the valve 92remains seated, producing suction in the conduit 53 and thecommunicating chamber C and in the suction pipe. At the same time, ifthere is liquid in the chamber B at the left of the piston, it is putunder pressure, the valve 8I remaining closed and the valve 8| opening,and thus liquid is forced into the passageway I2 and up the dischargepipe 90.

On the return stroke, toward the right, the liquid which has filled thechamber A is put under pressure, the valve 82 seats and the valve 92opens and such liquid is forced up into the passageway I2 and out of thepipe 90. On this right hand stroke the pressure in the chamber B at theleft of the piston is reduced, the valve 9i seating, the valve 9|opening, and liquid from the suction conduit passing through the ports15 and 12 into the chamber B, to be put under pressure on the subsequentleft hand stroke of the piston.

It is to be understood that the suction pipe 25 is provided with asuitable foot valve not shown, opening toward the pump and effective toretain the fluid in the chamber C on the left hand stroke ofthe piston.

vIn the embodiment illustrated in Figs. 5., 6 and 7, the cylinder withits heads; the discharge valve features; thesupporting brackets, and theoperating mechanism, are all the same as that already described and thesame .reference characters apply. The construction in this modificationdiers merely in the piston and the valves therein.

As will be clearly seen from Fig. 5, I have in this embodiment provideda disc-like piston body III! which may be integral with the two' pistonrods 5I and 52. This body engages the wall of the piston and has aperipheral groove in which seats a packing II I. 0n opposite sides ofthe body III), above the piston rods, I have formed the constructioninto a pair of upwardly facing vertical chambers or cups II2 and VI I3which constitute valve chambers. Each chamber has its own port III, Ii5communicating with the bore 53 of the hollow piston rod. Each chambercommunicates individually with the space on that side of the piston rod,this communication being readily effected by terminating the tops of thechambers short of the cylinder wail.

The two valve chambers contain ball valves I IG, II1 controlling therespective ports II4 and II5. The chambers extend vertically upward sothat the balls normally rest by gravity on the seats, closing the ports.They may be moved upwardly away from the seat by fluid pressure but areretained within the cavity by cross rods IIS mounted in the walls of thecavity. l

The construction of Fig. 5 is somewhat cheaper than that of Fig. 2 andis equally effective 'especially in installations where it is feasiblefor the wall cavities to retain the upwardly extending position. Theoperation offthis embodiment is essentially the same as that of Fig. 2,namely, when the piston moves toward the left, the valve IIS remainsseated due to the pressure on it, while the valve I I1 lifts, due to thereduced pressure in the right hand portion of the cylinder. Thissupplies suction to allow the fluid to flow to the pump through the bore53. Then, on the return stroke toward the right, the valve II1 is seatedand the valve IIB lifts and allows fluid to pass into the left handcylinder space.

It results therefore that as the handle is reciprocated back and forth,fluid is forced upward-4 v well adapted for pumping fluid under pressureas an emergency hand operation in airplanes in the case of failure ofthe automatic pumping. The mechanism shown with its effective packingenables the ready pumping of such fluid under high pressure.

One of the objects of my invention, especially useful in airplane work,is to enable the ready disassemblage of the parts for cleaning or forreplacement of any broken or injured part. Thus by merely unscrewing thenut 69 and taking out the bolt 65, I can disconnect the operatingmechanism from the piston. Then by detaching one of the frame membersfrom its support, by the removal of the fastening bolts passing throughthe feet thereof, and the removal of the nuts 42 on the rods 40, I canseparate the frame plates from the cylinder heads and allow the cylinderheads to be separated from the cylinder and the piston removed. Thisleaves each packing. duly exposed for the replacement. By taking out theplugs 94, one obtains access to each of the disciprocating the piston.

charge valves and by removing the abutment disc y 'I0 or the stop pinthe valves in the piston are freed for removal. It is a similarly simplematter to reassemble the pump. Accordingly, cleaning y or repairs may bereadily accomplished, as well as the replacement of any injured part.

I claim:

1. In a pump, the combination of a cylinder, a pair of heads therefor, apiston therein, a piston rod extending from the cylinder through one ofthe heads of the cylinder, a pair of frame brackets abutting oppositeends of the cylinder heads and having lateral extensions to provide asupport, through bolts on the outside of the cylinder connecting theframe brackets and operating to hold the cylinder and the two heads andthe two frame brackets as one stationary device.

2. In apump, the combination of a cylinder, a pair of cylinder headstherefor, a pair of brackets on the outer side of the heads, throughbolts tightening the two brackets against the heads and the headsagainst the cylinder, one of said brackets being flanged at its lowerend to provide a supporting foot for the pump. a piston within thecylinder having an operating rod extending through one of the heads intoposition above said foot, and manual operating means for the rod mountedon said foot.

3. In a pump, the combination of a cylinder, a pair of heads extendinginto the interior of the cylinder and having iianges engaging the endsof the cylinder, through bolts on the outside of the cylinder adapted toforce the heads toward each other, a piston within the cylinder having arod slidable in one of the heads, said head having packings engaging theinterior of the cylinder and,

the exterior of said piston rod.

4. In a pump, the combination of a vcylinder having cylinder heads, apiston therein having a tubular portion extending slidably into one ofthe heads into communication with a supply conduit carried thereby, saidpiston having a pair of opposed radial chambers within it,each/communicating by a port at the bottom of the chamber with theinterior of said tubular portion, there being a port leading from onechamber to the space on one side of the piston and a port leading fromthe other chamber to the space on the other side of the piston, a ballvalve in each radial chamber adapted to seat over the port connect- 5.In a pump, the combination of a cylinder, a piston in the cylinderhaving a pair of chambers spaced longitudinally of the piston extendingoutwardly to the periphery of the piston, a packing carried by thepiston between said chambers, one of said chambers communicating withthe space in the cylinder on one side of the piston and the other withthe space from the cylinder on the other side of the piston, a tubularmember leading from the piston passing through one of the cylinder headsand in communication with a supply pipe, there being ports within thepiston from the respective chambers to said tubular member, each portbeing normally closed by aV valve within the chamber, valve-controlleddischarge passageways leading from the opposite ends of the cylinder,and means for reciprocating the piston.

6. In a pump, the combination of a cylinder having cylinder heads, apiston therein having a tubular portion extending slidably into one ofthe heads into communication with a. supply conduit, said piston havinga pair of upwardly extending chambers side by side longitudinally withthe piston extending between them, a packing carried by the pistonbetween said chambers each chamber communicating by la port with theinterior of said tubular portion, each chamber terminating short of thecylinder wall and thus in open communication across the periphery of thepiston with the cylinder space on that side of the piston, a valve ineach chamber, vaivecontrolied discharge passageways from the oppositeends of the cylinder, and means for reciprocating the piston. 1

7. In a pump, the combination of a cylinder, a pair of heads extendinginto the interior of the cylinder and having flanges engaging the endsof the cylinder, means passing through the flanges to hold the heads inposition, a piston within the cylinder having a rod slidable in one ofthe heads, said head having packings'engaging the interior of thecylinder and the exterior of said piston rod.

8. In a pump, the combination of a cylinder, a pair of heads extendinginto the interior of the cylinder and having flanges engaging the endsof the cylinder, a piston within the cylinder havlng a pair ofoppositely extending rods .slidable in the respective heads, operatingmeans engaging one of the rods. the other rod being tubular and asuction chamber in the head that rod occupies adapted to supply iiuid tothe tubular rod, there being passageways in the piston from the tubularrod to the opposite sides of the piston respectively, and valves withinthe piston controlling said passageways, each cylinder head havingpackings engaging the interior of the ing that chamber with the tubularmember, a I

cylinder and the exterior of the corresponding piston rod.

mELs A. CHRISTENSEN.

